In my opinion it's fine to teach bitcoin to kids as early as they can understand and adopt it, because bitcoin is constantly getting more and more valuable as the time goes by, while also increasing its support worldwide.
Just imagine if kids adopted bitcoin years ago and played online games which rewarded free satoshis as prizes. That would have been great and also a big boost for executing plans which demand financial resources they want to achieve when growing older.
I believe we could say bitcoin is an upgrade of the old good piggy bank, where kids were used to deposit every cents, saving for their future.
Good explanation@uneng, Bitcoin will serve as an upgraded piggy bank if the kids are well taught about It.
Apart from that, it will also help to reduce their total reliance on fiat currency, so I encourage every parent to equip their kids with bitcoin knowledge hence they can operate computers and phones.